In realizing electronic components, for example, a radio-frequency micro-electromechanical system (RF-MEMS) variable capacitance using MEMS techniques and an electrostatic actuator applied to RF-MEMS switches have been developed. The electrostatic actuator has the problem of being slow in switching speed. An electrostatic actuator with a driving voltage of about 20 V has a switching time as slow as about 20 μs, which narrows the range of application of RF-MEMS.
The driving voltage of the electrostatic actuator is generated by a step-up circuit provided in a semiconductor device (e.g., refer to JP 2004-112944). To shorten the switching time of the electrostatic actuator, the driving voltage has to be raised. However, it takes time to generate a high voltage with the step-up circuit of the semiconductor device. Accordingly, it is difficult to shorten the total time required for the switching of the electrostatic actuator. In addition, if the electrostatic actuator is driven at a high voltage, the number of stictions due to charging increases, which makes faults liable to occur. Therefore, it has been demanded that a high voltage necessary to drive an electrostatic actuator in a short time can be generated and charging is made less liable to occur.